1. Technical Field
The present disclosure relates to an imaging apparatus, an imaging system that includes the imaging apparatus, an electron mirror system that includes the imaging apparatus, and a ranging apparatus that includes the imaging apparatuses.
2. Description of the Related Art
In the field of in-vehicle cameras, Japanese Unexamined Patent Application Publication No. 2010-25915, for example, discloses an imaging apparatus that includes polarizers disposed in an optical path of a compound-eye camera, and the polarizers are disposed such that the directions of their polarization axes differ from one another, in order to detect the road condition or lanes.
In addition, as cameras in the medical and cosmetic fields, such as an endoscope system and a skin analyzer system, imaging apparatuses that obtain both unpolarized light images and polarized light images are in practical use. Such an imaging apparatus includes a polarized illuminator that irradiates biological tissues with unpolarized light and light that vibrates in the direction of a predetermined polarization axis. When a biological tissue is irradiated with light of a predetermined polarization component, light reflected by the surface of the biological tissue results in specular reflection light in which the polarization component is retained, and light reflected by a deeper portion of the biological tissue results in diffuse reflection light having chaotic polarization components. Accordingly, images of the surface of the biological tissue and of the deeper portion of the biological tissue can be obtained by providing the imaging apparatus with a polarization filter that transmits light which vibrates in the direction parallel to the polarization axis of the polarized illuminator and another polarization filter that transmits light which vibrates in the direction orthogonal to the polarization axis of the polarized illuminator.
For example, Japanese Unexamined Patent Application Publication No. 2008-237243 and Japanese Unexamined Patent Application Publication No. 2011-97987 disclose imaging apparatuses for obtaining images having different polarization characteristics.